Biologic Effects of Radiation and Risk Evaluation from Radiation Exposure Interaction of radiation with biologic systems results in a variety of biologic changes that can be either deleterious or benign….
Pyoderma Gangrenosum Campbell L. Stewart Roberto Novoa DEFINITION Pyoderma gangrenosum (PG) is a rare, ulcerative cutaneous disease of unknown etiology. Its diagnosis critically relies upon the exclusion of other causes…
Detectability or Final Contrast in an Image An imaging devise should ideally detect the smallest possible localized or focal abnormalities (lesions) that may be present in an organ. Because of…
Granuloma Annulare–Like Reactions Karolyn A. Wanat Misha Rosenbach INTRODUCTION Cutaneous granulomatous inflammation has been reported in association with underlying lymphoproliferative disorders in primarily two patterns: granulomas within or surrounding the…
Positron Emission Tomography (PET) In this chapter, we elaborate on the principles of PET, including instrumentation, relevant physical phenomena and corrections in image reconstruction, and quality assurance. As was discussed…
Cryoglobulinemia Alejandro A. Gru DEFINITION Cryoglobulins are abnormal serum immunoglobulins that reversibly precipitate at low temperature. Two forms of cryoglobulinemias are distinguished based on the composition of the cryoglobulins and…
Single-Photon Emission Computed Tomography This chapter provides an in-depth overview of SPECT, including instrumentation, quality assurance, as well as compensation methods for image reconstruction. Two overall methods for data acquisition…
Paraneoplastic Pemphigus Milda Chmieliauskaite Faizan Alawi INTRODUCTION Paraneoplastic pemphigus (PNP) is an autoimmune vesiculobullous disorder.1 PNP was first described in 1990 as a distinct clinical entity different from pemphigus vulgaris…
Emission Computed Tomography (ECT), General Principles Two-dimensional imaging, even with multiple views, does not provide accurate three-dimensional information concerning radionuclide distribution. Because two-dimensional imaging more or less integrates the information…
Vasculitis Alejandro A. Gru INTRODUCTION Vasculitis refers to a heterogeneous group of disorders characterized by vessel inflammation.1 The clinical manifestations range from locoregional ischemic and purpuric injuries to systemic disease….
